JP2013121385A - Electrode catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode catheter, capable of irrigating the surface of a tip electrode with liquid supplied from a lumen of an eccentrically-formed catheter shaft uniformly in the circumferential direction.SOLUTION: The electrode catheter includes a catheter shaft 10 having an eccentrically-formed lumen 11 serving as a path for fluid, an irrigation member 20 connected to the tip side of the shaft, a tip electrode 30 connected to the tip side of the member, and a ring-shaped electrode 40. The electrode catheter further includes a plurality of irrigation holes 25A disposed on the irrigation member 20 at equiangular intervals; and receiving grooves 215, 225 for housing a lead line 40L of the ring-shaped electrode 40, which are formed on the outer peripheral surface of a rear edge-side linear body part of the irrigation member 20 that is fitted to a tip-side recess 15 of the shaft 10.

Description

  The present invention relates to an electrode catheter, and more particularly to an electrode catheter having an electrode attached to the tip of the catheter and a mechanism for irrigating a liquid such as physiological saline to the electrode.

  In an ablation catheter that is an electrode catheter, an ablation catheter having an irrigation mechanism for cooling a tip electrode that has become hot during cauterization is used.

  As a conventional catheter equipped with an irrigation mechanism, a catheter that injects physiological saline supplied into the tip electrode through a catheter shaft from a plurality of openings formed on the surface of the tip electrode has been introduced. (For example, refer to Patent Document 1 and Patent Document 2).

  However, conventionally known catheters in which an irrigation opening is formed on the surface of the tip electrode have the following problems (1) to (4).

(1) When an opening is provided on the surface of the tip electrode, an edge is inevitably formed at the opening edge or the like. When cauterization is performed with the tip electrode having such an edge, the current density in the edge portion becomes extremely high, and an abnormal temperature rise occurs in this portion, so that a thrombus may be rapidly formed. .
(2) Even if physiological saline is injected from the opening formed on the surface of the tip electrode, sufficient irrigation cannot be performed on the surface of the tip electrode (the surface cannot be covered with a liquid). In particular, in the catheters described in Patent Document 1 and Patent Document 2 that inject physiological saline in a direction perpendicular to the axis of the tip electrode, the saline cannot be sufficiently brought into contact with the surface of the tip electrode. .
(3) By forming a plurality of openings on the electrode surface, it is impossible to ensure a sufficient surface area of the tip electrode, and efficient cauterization treatment cannot be performed.
(4) The tip electrode constituting the ablation catheter is usually provided with a temperature sensor, and ablation treatment is performed while monitoring and controlling the temperature of the tip electrode and surrounding tissue. However, in the catheters described in Patent Document 1 and Patent Document 2 described above, the tip electrode is cooled more than necessary by the physiological saline supplied to the inside (flow path) of the tip electrode, and the inside of the tip electrode is placed inside the tip electrode. There is a problem that the temperature sensor provided cannot accurately monitor and control the temperature during ablation treatment. In order to solve such a problem, an irrigation member made of a heat insulating material is provided between the tip electrode on which the temperature sensor is arranged and the catheter shaft, and the tip electrode is cooled more than necessary by physiological saline. A technique for preventing this is introduced (see Patent Document 3).

Japanese Patent No. 2562681 JP 2006-239414 A Special table 2009-537243

(1) In an electrode catheter in which a plurality of ring-shaped electrodes are mounted on the outer peripheral surface of the distal flexible portion of the catheter shaft together with the distal electrode, lead wires are connected to the distal electrode and the ring electrode, respectively.
The lead wire of the ring electrode is welded to the inner peripheral surface of the ring electrode at each tip portion, and is arranged on the outer peripheral surface of the tip flexible portion corresponding to the mounting position of the ring electrode. The lumen enters the lumen of the catheter shaft through the hole, extends into the lumen and the inner hole of the control handle, and is connected to the connector at each rear end (see, for example, paragraph 0029 of JP-A-2006-255401).

  Thus, in an electrode catheter equipped with a ring-shaped electrode, monitoring the bipolar potential between the first pole (tip electrode) and the second pole (first ring-shaped electrode from the tip) is a clinical viewpoint. is important. Here, the separation distance (electrode interval) between the first pole and the second pole is preferably about 2 mm.

  However, like the electrode catheter described in Patent Document 3, the irrigation member is connected to the distal end side of the catheter shaft by inserting the rear end portion (rear end side straight body portion) of the irrigation member into the distal end portion of the catheter shaft. When the irrigation member is provided between the distal electrode and the catheter shaft, the lumen is removed from the distal end portion of the catheter shaft into which the rear end portion of the irrigation member is inserted (insertion portion of the rear end portion of the irrigation member). Since the lead wire cannot be inserted into the ring electrode, the ring electrode cannot be attached to the outer peripheral surface of the distal end portion of the catheter shaft, and the second pole (the first ring electrode from the tip) is the irrigation member. It is mounted on the outer peripheral surface on the base end side with respect to the insertion portion of the rear end portion. As a result, the separation distance between the first pole and the second pole becomes long (for example, 5 mm or more), and depending on such an electrode catheter, a local potential change is measured between the first pole and the second pole. Therefore, there is a problem that the accuracy of specifying the lesion on the distal end side of the catheter is lowered.

(2) A leaf spring is frequently used as a deflection mechanism for performing a catheter tip deflection operation. Such a leaf spring is disposed along the central axis of the catheter shaft at the distal flexible portion of the catheter shaft. By adopting a leaf spring as the deflection mechanism, sufficient torsional rigidity is imparted to the distal end flexible portion, and operability as a catheter capable of deflecting the distal end is improved.

However, when a deflection mechanism using a leaf spring is employed in an electrode catheter equipped with an irrigation mechanism, a lumen serving as a physiological saline flow path can be formed along the central axis at the flexible portion of the distal end of the catheter shaft. First, it must be formed eccentric from the central axis.
Furthermore, since the physiological saline flow path in the tip electrode or irrigation member connected to such a catheter shaft is also formed eccentrically from the central axis, the physiological saline has an eccentric opening (exit of the flow path). Will be injected from.
As described above, there is a problem that the physiological saline sprayed from the eccentric opening through the eccentric flow path cannot be uniformly irrigated in the circumferential direction of the tip electrode.

In order to solve such a problem, it is conceivable to increase the number of ejection openings (flow channel outlets) arranged in the tip electrode or the irrigation member to make the circumferential direction uniform.
However, in order to increase the number of ejection openings (flow channel outlets), the number of flow channels formed in the tip electrode or irrigation member, and hence the number of lumens forming the flow channels formed in the catheter shaft, is increased. It is not realistic because it needs to be made.

The present invention has been made based on the above situation.
The object of the present invention is that an abnormal temperature rise (high temperature part) does not occur in a part of the tip electrode during cauterization, and it is excellent in the cooling effect of the tip electrode surface and the thrombus formation suppression effect on the tip electrode surface, and is efficient. To provide an electrode catheter in which at least one ring-shaped electrode is attached to the outer peripheral surface of the distal end portion of the catheter shaft into which the rear end portion of the irrigation member is inserted. is there.
Another object of the present invention is to provide an electrode catheter capable of uniformly irrigating the liquid from the lumen of the catheter shaft formed eccentrically in the circumferential direction with respect to the surface of the tip electrode.

[1] The electrode catheter of the present invention has a distal end flexible portion, and a catheter shaft in which at least one lumen serving as a liquid flow path is formed eccentrically in the distal end flexible portion, and the distal end side of the catheter shaft An electrode catheter comprising an insulating irrigation member connected to the distal end of the insulating irrigation member, and a distal electrode connected to the distal end side of the insulating irrigation member,
In the insulating irrigation member, a plurality of irrigation openings for irrigating the surface of the tip electrode with liquid supplied from the catheter shaft are arranged at equiangular intervals along the outer periphery of the insulating irrigation member. ,
At least one ring-shaped electrode is attached to the outer peripheral surface of the distal end flexible portion of the catheter shaft,
In the catheter shaft, at least one lumen serving as an insertion passage for the lead wire of the ring electrode is formed eccentrically at the distal end flexible portion, and the lumen serving as the liquid flow path and the ring electrode A tip side recess is formed with the tip end surface where each of the lumens serving as lead wire insertion passages is open,
The insulating irrigation member is connected to the distal end side of the catheter shaft by fitting the rear end side straight body portion of the insulating irrigation member to the distal end side recess of the catheter shaft,
On the outer peripheral surface of the rear end side straight body portion of the insulating irrigation member, a lead storage groove for storing the lead wire of the ring electrode is formed along the axial direction,
Among the ring electrodes, at least the lead wire of the first ring electrode from the tip is connected to the ring electrode by being joined to the inner peripheral surface of the ring electrode at the tip. Then, it enters the lead receiving groove of the insulating irrigation member from the side hole formed in the outer peripheral surface of the distal end side concave portion of the catheter shaft corresponding to the mounting position of the ring-shaped electrode, and passes through the lead storing groove And it is penetrated by the lumen used as the insertion path of the lead wire of the said ring-shaped electrode, It is characterized by the above-mentioned.

  (A) According to the electrode catheter having such a configuration, since the irrigation opening is formed in the insulating irrigation member, it is not necessary to form an opening in the tip electrode, and there is no edge associated with the formation of the opening. In addition, an abnormal temperature rise does not occur in a part of the tip electrode during cauterization, thereby suppressing thrombus formation. Moreover, since it is not necessary to form an opening in the tip electrode, a sufficient surface area can be ensured, and efficient ablation treatment can be performed.

  (B) Since the liquid is irrigated from the insulating irrigation member to the surface of the tip electrode, a sufficient amount of liquid can be brought into contact with the surface of the tip electrode, and the surface of the tip electrode is irrigated. Since the liquid flows along the surface of the tip electrode from the base end portion of the tip electrode to the tip portion, the liquid is excellent in the cooling effect on the surface of the tip electrode, and the blood in the vicinity of the tip electrode surface is sufficiently stirred. An excellent effect of inhibiting thrombus formation is also obtained by dilution.

  (C) Since a plurality of irrigation openings arranged at equal angular intervals along the outer periphery of the insulating irrigation member are formed, irrigation can be performed over the entire area in the circumferential direction with respect to the surface of the tip electrode. .

  (D) Furthermore, a lead storage groove for storing the lead wire of the ring-shaped electrode is formed on the outer peripheral surface of the rear end side straight body portion of the insulating irrigation member, and at least the first ring-shaped electrode from the front end The lead wire enters the lead receiving groove of the insulating irrigation member from the side hole formed in the outer peripheral surface of the concave portion on the distal end side of the catheter shaft, and passes through the lead receiving groove to the lumen (ring-shaped) of the catheter shaft. At least one ring-shaped electrode on the outer peripheral surface of the distal-side concave portion of the catheter shaft into which the rear end-side straight body portion of the insulating irrigation member is inserted. Can be attached.

  (E) Further, in the distal end flexible portion of the catheter shaft, the lumen serving as the liquid flow path and the lumen serving as the insertion path for the lead wire of the ring-shaped electrode are formed eccentrically, thereby providing a conventional irrigation member. A leaf spring that could not be placed with an irrigation catheter can be placed along the central axis of the catheter shaft.

[2] In the electrode catheter of the present invention, in the insulating irrigation member, at least one eccentric flow channel communicating with a lumen serving as a liquid flow channel of the catheter shaft;
A space communicating with the eccentric flow path, and a liquid storage space having no partition wall in the circumferential direction so that the liquid from the eccentric flow path is uniformly distributed in the circumferential direction of the insulating irrigation member; ,
A plurality of branch flow paths communicating with the storage space and extending in the distal direction while inclining outward and reaching each of the plurality of irrigation openings are formed,
A liquid guide groove extending in the distal direction from each of the plurality of irrigation openings is formed in the distal end portion of the insulating irrigation member continuously to each of the plurality of branch channels.
It is preferable that a liquid guide groove that is continuous with each of the guide grooves of the insulating irrigation member is formed at the base end portion (base end surface) of the tip electrode.

  (A) According to the electrode catheter having such a configuration, the eccentric flow path is formed inside the insulating irrigation member, so that the liquid from the lumen of the catheter shaft (the liquid flow path formed eccentrically) Can be distributed toward the storage space.

  (B) Further, inside the insulating irrigation member, a liquid storage space that does not have a partition wall in the circumferential direction thereof, communicates with the storage space, and extends in the distal direction while inclining outward, and has a plurality of irrigation openings. By forming a plurality of branched flow paths reaching each, the liquid that has reached the storage space through the eccentric flow path is arranged so that the flow is evenly distributed in the circumferential direction in the storage space. Since the irrigation openings are ejected (irrigated) through each of the plurality of branch channels extending in the distal direction, there is a variation in the amount of liquid ejected between the plurality of irrigation openings arranged at equiangular intervals. In addition, uniform injection (irrigation) can be performed in the circumferential direction of the insulating irrigation member, and the surface of the tip electrode can be evenly irrigated over the entire circumferential direction.

  (C) Furthermore, an irrigation opening (branch channel) is formed by forming the branch channel formed inside the insulating irrigation member so as to be inclined outward (outside in the radial direction of the insulating irrigation member). Can be irrigated even on the surface of a tip electrode (eg, a tip electrode having a diameter equal to or larger than the diameter of the tube of the catheter shaft). .

(D) Furthermore, a liquid guide groove extending in the distal direction continuously to each of the plurality of branch channels is formed at the distal end portion of the insulating irrigation member, so that the liquid ejected from the irrigation opening ( The liquid that has reached the irrigation opening through the branch channel can be reliably guided (guided) toward the tip electrode.
(E) Furthermore, a liquid guide groove that is continuous with each of the guide grooves of the insulating irrigation member is formed on the surface of the base end portion of the tip electrode, so that the guide groove formed in the insulating irrigation member passes through the guide groove. Thus, the liquid that has reached the proximal end portion of the distal electrode can be guided (guided) to the distal end portion of the distal electrode, whereby the liquid can be supplied to the entire surface of the distal electrode.

[3] The electrode catheter of [2] preferably includes a leaf spring extending along the central axis of the catheter shaft as a deflection mechanism for bending the distal flexible portion of the catheter shaft.

  The electrode catheter having such a configuration is excellent in operability by imparting sufficient torsional rigidity to the flexible portion of the distal end of the catheter shaft. In addition, according to this electrode catheter, although the leaf spring is arranged along the central axis of the catheter shaft and the lumen serving as the liquid flow path is formed eccentrically, the circumference of the tip electrode surface is reduced. Can be irrigated uniformly in the direction.

[4] In the electrode catheter of [2] or [3] above, the lumen serving as the liquid flow path of the catheter shaft and the eccentric flow path of the insulating irrigation member communicate with each other via a joint tube. Is preferred.

  According to the electrode catheter having such a configuration, the insulating irrigation member can be reliably connected to the distal end side of the catheter shaft, and the distal end surface of the catheter shaft (the distal end where the lumen serving as the liquid flow path opens) Surface) and the rear end surface of the insulating irrigation member (rear end surface where the eccentric flow path opens) can prevent liquid leakage (liquid intrusion into the shaft accompanying this).

[5] In the electrode catheter according to any one of [2] to [4], the number of eccentric flow paths formed inside the insulating irrigation member is 1 or 2, and the number of branch flow paths is 4 or more. It is preferable that
When the number of eccentric flow paths formed inside the insulating irrigation member is 1 or 2 (that is, when the number of lumens serving as liquid flow paths of the catheter shaft is 1 or 2, the tip of the catheter shaft It is particularly effective to install an insulating irrigation member on the side [circulating the liquid supplied from the catheter shaft into the insulating irrigation member (eccentric flow path, storage space, multiple branch flow paths)]. is there.
Moreover, if the number of branch flow paths (the number of irrigation openings) is 4 or more, irrigation can be sufficiently uniformly performed in the circumferential direction of the insulating irrigation member.

[6] In the electrode catheter of any one of [2] to [5], the lead receiving groove is formed in the order of a shallow groove portion, an inclined groove portion, and a deep groove portion so as to become deeper toward the rear end direction. Is preferred.

[7] In the electrode catheter of [6], it is preferable that the inclined groove portion and the deep groove portion of the lead storage groove are formed on the rear end side from the storage space.

According to the electrode catheter having such a configuration, the lead accommodating groove (shallow groove portion) extending in the same axial position as the position where the plurality of branch flow paths and the storage space are formed can be formed relatively shallow. The lead storage groove (shallow groove portion) can be formed so as to avoid the flow path and the storage space.
On the other hand, although the lumen serving as the insertion path for the lead wire of the ring electrode in the catheter shaft is formed eccentrically, it may be formed inside the bottom surface of the shallow groove portion of the lead storage groove. Depending on the lead storage groove extending in the rear end direction, the lead wire may not be guided to the lumen. Even in such a case, according to the electrode catheter including the insulating irrigation member in which the inclined groove portion and the deep groove portion of the lead storage groove are formed on the rear end side from the storage space, the lead storage groove After the lead wire extending in the rear end direction along the inward direction is directed inward by the inclined groove portion, it can be guided through the deep groove portion to the lumen of the catheter shaft (the lumen serving as an insertion path for the lead wire of the ring electrode).

[8] In the electrode catheter of [6] or [7] above, the lead wire of the first ring-shaped electrode from the distal end is the first side formed on the outer peripheral surface of the distal-end-side recess of the catheter shaft. Enter the shallow groove portion of the lead storage groove from the hole,
The lead wire of the second ring-shaped electrode from the distal end enters the deep groove portion of the lead receiving groove from the second side hole formed in the outer peripheral surface of the distal-end-side recess of the catheter shaft. preferable.

  According to the electrode catheter having such a configuration, the outer end surface of the catheter shaft into which the rear end portion (rear end side straight body portion) of the insulating irrigation member is inserted is inserted from the front end to the outer peripheral surface of the catheter shaft. First and second ring electrodes can be mounted.

[9] In the electrode catheter according to any one of [2] to [8], the insulating irrigation member has a central through hole formed along a central axis thereof, and a central tube is formed in the central through hole. It is preferable that it is inserted.

[10] In this case, it is preferable that the lead wire of the tip electrode and / or the lead wire of the temperature sensor is inserted into the central tube.

  According to the electrode catheter having such a configuration, it is possible to reliably prevent the lead wire inserted into the central tube from coming into contact with the liquid.

[11] In the electrode catheter of the present invention, the tip of the tip electrode bulges, and when the maximum diameter of the tip electrode is D1 and the tube diameter of the catheter shaft is D2, the value of D1 / D2 is 1. It is preferably 0 or more.

  According to the electrode catheter having such a configuration, a sufficient surface area for ablation treatment can be secured at the distal electrode.

  According to the electrode catheter of the present invention, an abnormal temperature rise does not occur in a part of the tip electrode during cauterization, and the tip electrode surface cooling effect and the thrombus formation suppression effect on the tip electrode surface are excellent and efficient. A cautery treatment can be performed.

  According to the electrode catheter of the present invention, the liquid from the lumen of the catheter shaft formed eccentrically can be uniformly irrigated in the circumferential direction with respect to the surface of the tip electrode. In addition, since the lumen serving as the liquid flow path is formed eccentrically at the distal end flexible portion of the catheter shaft, the leaf spring that could not be arranged by the conventional irrigation catheter having the irrigation member is disposed at the center of the catheter shaft. It becomes possible to arrange | position along an axis | shaft.

  According to the electrode catheter of the present invention, at least one ring is further provided on the outer peripheral surface of the distal end portion (distal end side recess) of the catheter shaft into which the rear end portion (rear end side straight body portion) of the insulating irrigation member is inserted. A shaped electrode can be mounted.

It is a front view of the ablation catheter which concerns on one Embodiment of the electrode catheter of this invention. It is a longitudinal cross-sectional view in the front-end | tip part of the ablation catheter shown in FIG. It is a cross-sectional view (CC cross-sectional view of FIG. 2 (FIG. 7)) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (FIG. 2 (FIG. 7) BB sectional view) in the front-end | tip part of the ablation catheter shown in FIG. It is a cross-sectional view (DD sectional view of Drawing 2 (Drawing 7)) in the tip part of the ablation catheter shown in Drawing 1. It is a cross-sectional view (AA sectional view of FIG. 2 (FIG. 7)) at the distal end portion of the ablation catheter shown in FIG. It is a longitudinal cross-sectional view (FF sectional drawing of FIG. 3) in the front-end | tip part of the ablation catheter shown in FIG. It is a perspective view which shows the irrigation member which comprises the ablation catheter shown in FIG. It is a perspective view which shows the irrigation member which comprises the ablation catheter shown in FIG. It is a longitudinal cross-sectional view (GG sectional drawing of FIG. 4) in the front-end | tip part of the ablation catheter shown in FIG. It is a cross-sectional view (HH cross-sectional view of FIG. 10) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (II cross-sectional view of FIG. 10) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (JJ cross section of FIG. 10) in the front-end | tip part of the ablation catheter shown in FIG.

Hereinafter, an embodiment of an electrode catheter of the present invention will be described with reference to the drawings.
The electrode catheter shown in FIGS. 1 to 7 and FIGS. 10 to 13 is an ablation catheter of the present invention used for treatment of arrhythmia in the heart.

The ablation catheter 100 of this embodiment has a distal end flexible portion 10A, and a catheter shaft 10 in which two lumens 11 and 11 serving as liquid flow paths are eccentrically formed in the distal end flexible portion 10A, and the catheter. The insulating irrigation member 20 connected to the distal end side of the shaft 10, the distal electrode 30 connected to the distal end side of the irrigation member 20, and 3 attached to the outer peripheral surface of the distal end flexible portion 10 </ b> A of the catheter shaft 10. Two ring-shaped electrodes 40, tension wires 61, 62 constituting a deflection mechanism for deflecting the distal flexible portion 10A of the catheter shaft 10, and the tension wires 61, 62 disposed along the central axis of the catheter shaft 10. 62 and a leaf spring 65 constituting a deflection mechanism, and a control handle connected to the proximal end side of the catheter shaft 10 0, it includes an injection tube 80 of the liquid;
The distal end flexible portion 10A of the catheter shaft 10 is formed with two lumens 11 and 11 serving as liquid flow channels facing each other across the central axis (that is, each eccentric from the central axis). , Two lumens 12 and 12 serving as insertion passages for the pulling wires 61 and 62 and two lumens 13 and 13 serving as lead passages for the ring-shaped electrode 40 are formed; Eight irrigation openings 25A for ejecting (irrigating) the liquid supplied from the catheter shaft 10 onto the surface of the tip electrode 30 are arranged along the outer periphery of the irrigation member 20 at equiangular intervals (45 ° intervals).
Inside the irrigation member 20, there are two eccentric flow passages 23, 23 communicating with the lumens 11, 11 serving as liquid flow passages of the catheter shaft 10, and a space communicating with the eccentric flow passages 23, 23. In order for the liquid from the flow paths 23 and 23 to be uniformly distributed in the circumferential direction of the irrigation member 20, a liquid storage space 24 that does not have a partition wall in the circumferential direction and the storage space 24 are communicated and inclined outward. However, eight branch channels 25 extending in the distal direction and reaching each of the eight irrigation openings 25A are formed, and the tip of the irrigation member 20 is continuously connected to each of the eight branch channels 25. A liquid guide groove 26 extending in the distal direction from each of the irrigation openings 25A is formed;
A liquid guide groove 36 is formed on the surface of the proximal end portion of the tip electrode 30 so as to be continuous with each of the guide grooves 26 of the irrigation member 20;
The irrigation member 20 has a front-side recess 21A that can be fitted to the cylindrical portion 33 of the front-end electrode 30, and a recess 21B that is also formed on the rear-end side. And a first small diameter portion 221 that can be fitted in the rear end concave portion 21B of the first component 21, and two eccentric flow paths 23, 23 are formed inside. Constituted by fitting the second part 22 being made;
The depth (d ₂₁ ) of the rear end side recess 21B of the first component 21 is formed deeper than the length (d ₂₂ ) of the distal end side small diameter portion 221 of the second component 22, thereby The storage space 24 (the bottom surface (rear end surface) 21b and the inner peripheral surface of the rear end recess 21B of the first component 21) and the front end surface of the front end side small diameter portion 221 of the second component 22 at the fitting part with the second component 22 22a) is formed;
The catheter shaft 10 includes lumens 11 and 11 serving as liquid flow paths, lumens 12 and 12 serving as insertion paths for the pulling wires 61 and 62, and lumens 13 and 13 serving as insertion paths for the lead wire 40L of the ring electrode 40, respectively. A tip-side concave portion 15 having a bottom surface as a tip surface where the opening is opened;
By fitting the rear end side straight body portion (the straight body portion 213 of the first component 21 and the straight body portion 223 of the second component 22) of the irrigation member 20 into the distal end side recess 15, An irrigation member 20 is connected to the distal side;
On the outer peripheral surfaces of the rear end side straight barrel portions 213 and 223 of the irrigation member 20, there are lead storage grooves (storage grooves 215, shallow groove portions 225a, inclined groove portions 225b, deep groove portions 225c) for storing the lead wires of the ring-shaped electrode 40. ) Are formed along the axial direction;
The lead wire 40L of the first ring-shaped electrode 40 from the distal end extends from the first side hole formed in the outer peripheral surface of the distal-end-side concave portion 15 of the catheter shaft 10 to the shallow groove portion (storage groove 215) of the lead storage groove. Is inserted into the lumen 13 via the lead storage groove (storage groove 215, shallow groove portion 225a, inclined groove portion 225b, deep groove portion 225c);
The lead wire 40L of the second ring-shaped electrode 40 from the distal end enters the deep groove portion 225c of the lead storage groove from the second side hole formed in the outer peripheral surface of the distal end side recess 15 of the catheter shaft 10, The lead 13 is inserted through the lumen 13 via the lead storage groove (deep groove 225c).

  As shown in FIG. 1, the ablation catheter 100 includes a catheter shaft 10 having a flexible tip portion 10A, an irrigation member 20, a tip electrode 30, a ring electrode 40, a control handle 70, and a liquid injection tube 80. And comprising.

  The infusion tube 80 shown in FIG. 1 is connected to the catheter shaft 10 through the inside of the control handle 70, and liquid is supplied to the lumen 11 of the catheter shaft 10 through the infusion tube 80. Here, as the “liquid”, physiological saline can be exemplified.

  The control handle 70 shown in FIG. 1 is connected to the proximal end side of the catheter shaft 10 and includes a rotating plate 75 for performing a distal end deflection operation of the catheter.

The catheter shaft 10 constituting the ablation catheter 100 has a flexible distal end portion 10A.
Here, the “tip flexible portion” refers to a tip portion of the catheter shaft that can be bent (bent) by pulling a wire for tip deflection operation.

As shown in FIGS. 2 and 3, tension wires 61 and 62 for bending the tip flexible portion 10 </ b> A (tip tip deflection operation) are disposed on the catheter shaft 10 (lumens 12 and 12). The rear ends of the tension wires 61 and 62 are connected to a rotating plate 75 (see FIG. 1) of the control handle 70, respectively. On the other hand, the front ends of the tension wires 61 and 62 are fixed on the outer peripheral surface (wire housing groove 226) of the irrigation member 20 (second component 22).
For example, when the rotating plate 75 is rotated in the A1 direction shown in FIG. 1, the pulling wire 61 is pulled, and the distal end flexible portion 10A of the catheter shaft 10 is deflected in the arrow A direction and rotated in the B1 direction shown in FIG. When the plate 75 is rotated, the pulling wire 62 is pulled, and the distal end flexible portion 10A of the catheter shaft 10 is deflected in the arrow B direction.

As shown in FIG. 3, the distal end flexible portion 10 </ b> A of the catheter shaft 10 has the catheter shaft 10 on a plane perpendicular to the arrangement direction of the pulling wires 61 and 62 (the bending direction of the distal end flexible portion 10 </ b> A). A leaf spring 65 is disposed along the central axis.
By disposing the leaf spring 65 on the tip flexible portion 10A, anisotropy in the bending direction is ensured and sufficient torsional rigidity is imparted to the tip flexible portion 10A to improve operability during tip deflection operation. Can be achieved.

As shown in FIGS. 3 and 7, two lumens 11, 11 serving as liquid flow paths are formed on the distal flexible portion 10 </ b> A of the catheter shaft 10 so as to face each other across the central axis of the catheter shaft 10. Has been.
In addition, the two lumens 11 and 11 in the distal end flexible portion 10A may merge at the shaft portion on the proximal end side with respect to the distal end flexible portion 10A.
Further, as shown in FIG. 3, the distal end flexible portion 10A has two lumens 12 and 12 serving as insertion paths for the pulling wires 61 and 62, and a lead wire of the ring electrode 40 (not shown in FIG. 3). Are formed, two lumens 13 and 13 serving as insertion passages, a lumen 14 serving as a passage for the lead wire 30L of the tip electrode 30, and a lumen 16 serving as a passage for the lead wire 35L of the temperature sensor (thermocouple). Has been. Thus, the distal flexible portion 10A of the catheter shaft 10 has a so-called multi-lumen structure. However, the distal end side concave portion 15 having a single lumen structure is formed at the distal end of the distal end flexible portion 10A for joining with an irrigation member 20 described later.

  The catheter shaft 10 is made of a synthetic resin such as polyolefin, polyamide, polyether polyamide, polyurethane, nylon, or PEBAX (polyether block amide). The proximal end side of the catheter shaft 10 may be a blade tube obtained by braiding a tube made of these synthetic resins with a stainless steel wire.

The outer diameter of the catheter shaft 10 is preferably 1.0 to 3.0 mm, more preferably 1.6 to 2.7 mm, and 2.36 mm as a suitable example.
The length of the catheter shaft 10 is preferably 600 to 1500 mm, and more preferably 900 to 1200 mm.

In the ablation catheter 100, the ejection (irrigation) of the liquid onto the surface of the distal electrode 30 is performed by the irrigation member 20 located on the rear end side of the distal electrode 30.
8 and 9 are perspective views showing the shape of the irrigation member 20 constituting the ablation catheter 100. FIG.

  As shown in FIGS. 2 and 7 to 10, the irrigation member 20 is configured by fitting a first part 21 and a second part 22 together.

The second component 22 constituting the irrigation member 20 is formed of a molded body in which a straight body portion 223 and a distal end side small diameter portion 221 having an outer diameter smaller than the straight body portion 223 are integrally formed.
8 and 9, the front end side small-diameter portion 221 of the second component 22 does not appear on the drawings because it is fitted inside the first component 21 (rear end side recess 21 </ b> B).

  The outer diameter of the straight body portion 223 of the second component 22 is preferably 0.80 to 2.80 mm, more preferably 1.80 to 2.12 mm, and 1.96 mm if a suitable example is shown. . The outer diameter of the small-diameter portion 221 on the distal end side of the second component 22 is preferably 0.60 to 2.60 mm, more preferably 0.40 to 1.70 mm, and 1.45 mm if a suitable example is shown. .

  As shown in FIGS. 4, 5, 7, and 9, the second component 22 has a central through hole 224 formed along the central axis thereof, and the central axis on both sides of the central through hole 224. Eccentric flow paths 23, 23 extending in parallel with each other are formed. The central through-hole 224 and the eccentric flow paths 23 and 23 are through-holes extending from the front end surface 22a of the second component 22 (front end side small diameter portion 221) to the rear end surface 22b of the second component 22 (straight barrel portion 223).

As shown in FIG. 7, each of the openings of the eccentric flow paths 23, 23 in the rear end surface 22 b of the second part 22 (cross section BB in FIG. 2 shown in FIG. 4) is the distal end surface (FIG. 3). 2 is opposed to each of the openings of the lumens 11 and 11 in the CC cross section of FIG.
The lumens 11, 11 of the catheter shaft 10 and the eccentric flow paths 23, 23 of the irrigation member 20 (second part 22) communicate with each other via joint tubes 51, 51.
Thereby, the connection between the catheter shaft 10 and the irrigation member 20 can be ensured, and the distal end surface of the catheter shaft 10 (the opening surface of the lumens 11 and 11) and the rear end surface of the irrigation member 20 are rear end surfaces. It is possible to prevent leakage of liquid at a contact point with 22b (opening surfaces of the eccentric flow paths 23, 23), and further, penetration of liquid into the shaft accompanying this.

As shown in FIG. 7, the cross-sectional shape of the eccentric flow passages 23, 23 penetrating through the second part 22 (the straight body portion 223 and the distal end side small diameter portion 221) is from the inside of the straight body portion 223 to the distal end side small diameter portion 221. Immediately before reaching the inside (step portion indicated by 231 in FIG. 7), the shape changes from a circular shape to a substantially semicircular shape. Therefore, although the opening shape of the eccentric flow paths 23 and 23 in the rear end surface 22b (BB cross section of FIG. 2 shown in FIG. 4) is circular, the front end surface 22a (FIG. 5) of the second component 22 is circular. The opening shape of the eccentric flow paths 23 and 23 in the DD cross section in FIG. 2 is substantially semicircular.
In this way, by changing the cross-sectional shape of the eccentric flow paths 23, 23, the thickness (for example, a thickness of 60 μm or more) of the molding material that defines the eccentric flow paths 23, 23 at the distal end side small diameter portion 221 is ensured. be able to.

  Further, as shown in FIGS. 2, 8, and 9, on the outer peripheral surface of the second component 22 (straight barrel portion 223), wire accommodating grooves 226 for accommodating and fixing the tip portions of the tension wires 61 and 62 are provided. 226 is formed.

As shown in FIGS. 8 to 10 and FIG. 13, a storage groove 225 that can store the lead wire 40 </ b> L of the ring electrode 40 is formed on the outer peripheral surface of the second component 22 (straight body portion 223). Yes.
As shown in FIG. 10, the storage groove 225 is formed in the order of the shallow groove portion 225a, the inclined groove portion 225b, and the deep groove portion 225c from the front end toward the rear end direction.

Here, the width of the storage groove 225 is preferably 0.15 to 0.35 mm, and 0.26 mm if a suitable example is shown.
The depth of the shallow groove portion 225a of the storage groove 225 is preferably 0.10 to 0.20 mm, and 0.12 mm if a suitable example is shown.
Moreover, it is preferable that the depth of the deep groove part 225c of the storage groove 225 is 0.15-0.65 mm, and it will be 0.50 mm if a suitable example is shown.

  The first part 21 constituting the irrigation member 20 includes a straight body part 213, a large diameter part 212 having a larger outer diameter than the straight body part 213, and a reduced diameter part 211 that is reduced in diameter toward the distal end. It consists of a molded body formed in

  The outer diameter of the straight body portion 213 of the first component 21 is substantially the same as the outer diameter of the straight body portion 223 of the second component 22, and the outer diameter of the large diameter portion 212 is the same as the outer diameter of the catheter shaft 10. Substantially the same. The minimum outer diameter of the reduced diameter portion 211 of the first component 21 is substantially the same as the outer diameter of the neck portion 32 of the tip electrode 30.

As shown in FIGS. 2, 7, and 10, a front end side recess 21 </ b> A that can be fitted to the rear end portion (cylindrical portion 33) of the front end electrode 30 is formed on the front end side of the first component 21. . Further, a rear end side recess 21 </ b> B that can be fitted to the front end side small diameter portion 221 of the second component 22 is formed on the rear end side of the first component 21.
Here, the depth (indicated by d ₂₁ in FIG. 7) of the rear end side recess 21 B of the first component 21 is greater than the length (indicated by d ₂₂ in FIG. 7) of the distal end side small diameter portion 221 of the second component 22. Deeply formed.

  As shown in FIGS. 7 and 8, the first component 21 (the reduced diameter portion 211) has eight irrigation openings for injecting (irrigating) the liquid supplied from the catheter shaft 10 onto the surface of the tip electrode 30. 25A is arranged along the outer periphery of the irrigation member 20 at equiangular intervals (45 ° intervals).

Further, in the first component 21, eight branch flow paths 25 (in the irrigation openings 25A) extending in the distal direction while being inclined outward from the bottom surface (rear end surface) 21b of the rear end side recess 21B ( A through hole) is formed.
As shown in FIG. 6, the openings of the branch flow passage 25 in the bottom surface (rear end surface) 21 b of the rear end side recess 21 </ b> B are also arranged at equal angular intervals (45 ° intervals) along the circumferential direction of the irrigation member 20. ing.

Each of the eight branch flow paths 25 is formed so as to be inclined outward (outside in the radial direction of the irrigation member 20) with respect to the axial direction of the irrigation member 20.
Thereby, it is possible to sufficiently irrigate the surface of the tip electrode having a certain size.
Here, the inclination angle of the branch channel 25 is preferably 3 to 45 °, more preferably 5 to 13 °, and 7 ° if a suitable example is shown.

  In addition, a liquid guide groove 26 is formed in the distal end portion (the reduced diameter portion 211) of the first component 21 so as to be continuous with each of the eight branch flow paths 25 and extend in the distal direction from each of the irrigation openings 25A. ing.

  The irrigation member 20 (first component 21) is provided with eight branch channels 25, irrigation openings 25A, and eight liquid guide grooves 26 along the outer periphery of the irrigation member 20 at intervals of 45 °. However, in FIG. 7 showing the longitudinal section, only a part of it is visible.

  As shown in FIGS. 2, 6, 7 and 10, the first component 21 extends from the bottom surface (rear end surface) 21b of the rear end side recess 21B to the bottom surface (front end surface 21a) of the front end side recess 21A. As described above, the central through hole 214 is formed along the central axis of the first component 21.

The central through hole 214 of the first component 21 and the central through hole 224 of the second component 22 constitute a central through hole of the irrigation member 20.
As shown in FIGS. 2, 4 to 7 and 10 to 13, a central tube 54 is inserted into the central through hole (214, 224) of the irrigation member 20. Inside the central tube 54, the lead wire 30L of the tip electrode 30 and the lead wire 35L of the temperature sensor are inserted.

  As shown in FIGS. 8 to 12, four storage grooves 215 that can store the lead wires 40 </ b> L of the ring-shaped electrode 40 are formed on the outer peripheral surface of the first component 21 (the straight body 213). Are arranged at equal angular intervals (90 [deg.] Intervals) along the outer periphery.

Here, the width of the storage groove 215 is preferably 0.12 to 0.50 mm, and is 0.34 mm if a suitable example is shown.
Moreover, it is preferable that the depth of the storage groove 215 is 0.10-0.20 mm, and if it shows a suitable example, it will be 0.12 mm.

  As shown in FIGS. 2 and 7 to 10, in the irrigation member 20 formed by fitting the first component 21 and the second component 22, the straight body 213 of the first component 21 and the second component 22 are The straight body part 223 constitutes a rear end side straight body part (a rear end side straight body part of the irrigation member 20 fitted in the distal side recess 15 of the catheter shaft 10).

In the irrigation member 20, one of the four storage grooves 215 formed on the outer peripheral surface of the straight body portion 213 of the first component 21 and the outer peripheral surface of the straight body portion 223 of the second component 22 are provided. The formed storage grooves 225 are arranged on the same straight line, whereby the storage grooves 215 related to the first component 21 and the storage grooves 225 (the shallow groove portion 225a, the inclined groove portion 225b, and the deep groove portion 225c related to the second component 22 are arranged. ) Is formed on the outer peripheral surface of the rear end side straight body part (straight body part 213, straight body part 223).
Here, the storage groove 215 related to the first component 21 and the shallow groove portion 225a of the storage groove 225 related to the second component 22 form a shallow groove portion of the lead storage groove.
Further, the inclined groove portion 225 b of the storage groove 225 according to the second component 22 forms an inclined groove portion of the lead storage groove.
Further, the deep groove portion 225c of the storage groove 225 according to the second component 22 forms a deep groove portion of the lead storage groove.

As shown in FIG. 10, the inclined groove portion 225b and the deep groove portion 225c of the lead storage groove are formed on the rear end side from the storage space 24, and at the same axial position as the formation position of the branch flow path 25 and the storage space 24, Shallow groove portions (the storage groove 215 and the shallow groove portion 225a) of the lead storage groove are formed.
Since the shallow groove portions (the storage groove 215 and the shallow groove portion 225a) of the lead storage groove are formed relatively shallow, they do not interfere with the branch flow path 25 and the storage space 24.

As shown in FIG. 10, the lead wire 40L of the first ring-shaped electrode 40 from the tip is connected to the ring-shaped electrode 40 by being welded to the inner peripheral surface of the ring-shaped electrode 40 at the tip. And enters the shallow groove portion (housing groove 215) of the lead housing groove from the first side hole formed in the outer peripheral surface of the distal end side recess 15 of the catheter shaft 10, and this lead housing groove (housing groove 215). , The shallow groove portion 225a, the inclined groove portion 225b, and the deep groove portion 225c), and is inserted into the lumen 13 serving as an insertion path for the lead wire 40L.
Further, the lead wire 40L of the second ring electrode 40 from the tip is connected to the ring electrode 40 by welding to the inner peripheral surface of the ring electrode 40 at the tip, and the catheter The lead wire enters the deep groove portion 225c of the lead storage groove from the second side hole formed in the outer peripheral surface of the distal end side recess 15 of the shaft 10, and this lead wire passes through the lead storage groove (deep groove portion 225c). It is inserted through the lumen 13 serving as a 40 L insertion passage.

  Here, although the lumen 13 serving as an insertion path for the lead wire 40L is formed eccentrically, it is formed on the inner side of the bottom surface of the shallow groove portion (the storage groove 215 and the shallow groove portion 225a), and the shallow groove portion is formed at the rear end. The lead storage groove extending in the direction cannot guide the lead wire 40L to the lumen 13, but in this embodiment, the inclined groove portion 225b and the deep groove portion 225c of the lead storage groove are provided on the rear end side of the irrigation member 20. Since it is formed on the outer peripheral surface of the straight body portion (straight body portion 223), the lead wire 40L extending in the rear end direction through this lead storage groove can be guided to the lumen 13.

The first component 21 and the second component 22 constituting the irrigation member 20 are made of a molded body of an insulating resin or an insulating ceramic.
The first component 21 and the second component 22 are preferably made of a molded body obtained by a ceramic injection molding method (CIM).
According to the ceramic injection molding method, even a fine shape (for example, a fine shape having a thickness of about 60 μm) that cannot be formed by resin injection molding can be formed. The irrigation member 20 can be reliably molded.
Moreover, the ceramic molding obtained by the ceramic injection molding method has low thermal conductivity suitable as a constituent material of the irrigation member.
Further, the ceramic molded body by the ceramic injection molding method is excellent in insulation, and even when the irrigation member 20 made of this molded body has an edge, current is concentrated on the edge portion when the ablation catheter 100 is used (cauterization). And does not become hot.
As a suitable ceramic material constituting the irrigation member 20, it is preferable to use zirconia from the viewpoint of excellent molding processability and excellent biocompatibility.

The irrigation member 20 is configured by fitting a rear end side concave portion 21 </ b> B formed in the first component 21 and a front end side small diameter portion 221 of the second component 22.
In the fitting portion of the irrigation member 20, the bottom surface (rear end surface) 21b of the rear end side recess 21B of the first component 21 and the front end surface 22a of the second component 22 are separated by a distance of d ₂₁ -d _22. In the meantime, a jacket space partitioned by the inner peripheral surface of the rear end side recess 21B and the outer peripheral surface of the central tube 54 is defined, and this jacket space serves as a liquid storage space 24.

The storage space 24 formed in this way is a space for allowing the liquids from the eccentric flow paths 23, 23 to merge and uniformly distributing in the circumferential direction of the irrigation member 20. Since the storage space 24 has no circumferential partition, the liquid flowing into the storage space 24 can freely flow in the circumferential direction.
Here, the length (d ₂₁ -d ₂₂ ) of the storage space 24 is preferably 0.15 to 0.65 mm, and is 0.30 mm if a suitable example is shown.

  The irrigation member 20 configured as described above has two eccentric flow paths 23 and 23 formed inside the second component 21 so as to communicate with the lumens 11 and 11 of the catheter shaft 10 serving as a liquid flow path. And the first component 21 and the second component 22 so that the liquid from the eccentric channels 23 and 23 is uniformly distributed in the circumferential direction of the irrigation member 20. A liquid storage space 24 that does not have a partition wall in the circumferential direction formed in the fitting portion of the, and communicates with the storage space 24 and extends in the distal direction while inclining outward to reach each of the irrigation openings 25A. The eight branch channels 25 formed inside the first component, and the tip portion (first component) extending in the distal direction from each of the irrigation openings 25A continuously to each of the eight branch channels 25. The guide groove 26 of the liquid formed in the reduced diameter portion 211) It comes to have.

As shown in FIG. 7, the straight body part 213 and the second part 22 (the distal-side small diameter part 221 and the straight body part 223) of the first part 21 constituting the irrigation member 20 are inserted into the distal-side recessed part 15 of the catheter shaft 10. The distal ends of the catheter shaft 10 are (fitted), and the eccentric flow paths 23 and 23 of the irrigation member 20 are communicated with the lumens 11 and 11 of the catheter shaft via the joint tubes 51 and 51, respectively. The irrigation member 20 is connected to the side.
Thereby, only the reduced diameter portion 211 and the large diameter portion 212 of the first component 21 appear as the external shape of the irrigation member 20.

  On the other hand, the tip electrode 30 is connected to the tip side of the irrigation member 20 by fitting the cylindrical portion 33 of the tip electrode 30 into the tip side recess 21A of the irrigation member 20 (first component 21).

  The tip electrode 30 connected to the tip side of the irrigation member 20 and constituting the ablation catheter 100 has a hemispherical tip bulging portion 31, a neck portion 32, and a cylindrical portion 33.

  The diameter of the tip bulging portion 31 of the tip electrode 30 is preferably 1.0 to 3.3 mm, more preferably 2.2 to 2.6 mm, particularly preferably 2.3 to 2.5 mm. An example is 2.36 mm.

Further, when the diameter of the tip bulging portion 31 (the maximum diameter of the tip electrode 30) is D1 and the tube diameter of the catheter shaft 10 is D2, the value of D1 / D2 is preferably 1.0 or more, and more preferably. Is 1.0 to 1.5, and 1.0 (D1 / D2 = 2.36 mm / 2.36 mm) is shown as a preferable example.
When the value of D1 / D2 is too small, it is difficult to perform efficient cauterization treatment with a catheter provided with such a tip electrode.
On the other hand, when the value of D1 / D2 is excessive, it becomes difficult to irrigate a sufficient amount of liquid onto the surface of such a tip electrode.

  Note that a sufficient amount of liquid can be irrigated with respect to the surface of the tip electrode 30 having a value of D1 / D2 of 1.0 or more because the branch flow path 25 of the irrigation member 20 is inclined outward. This is because the irrigation opening 25 </ b> A is positioned on the outer side as compared with the case where it is not inclined. Also in this point, it is meaningful to interpose the irrigation member 20.

In addition, a liquid guide groove 36 that is continuous with each of the guide grooves 26 of the irrigation member 20 is formed at the proximal end portion (neck portion 32) of the distal electrode 30.
By forming the guide groove 36, the liquid that has reached the proximal end portion of the distal electrode 30 through the guide groove 26 formed in the irrigation member 20 is guided (guided) to the distal end portion of the distal electrode 30. Accordingly, the liquid can be supplied to the entire surface of the tip electrode 30 including the tip bulge portion 31.
Since the guide groove 36 formed in the tip electrode 30 has a gentle R shape, an abnormal temperature rise does not occur in this portion even during cauterization.

  According to the ablation catheter 100 of this embodiment, the irrigation opening 25A is formed in the insulating irrigation member 20, and the conductive tip electrode 30 has no edge, so that the ablation catheter 100 is used (cautery). ) Does not cause an abnormal temperature rise (high temperature part) in a part of the tip electrode 30, and it is possible to prevent blood from coming into contact with such a high temperature part and forming a thrombus. In addition, since there is no need to form an opening in the tip electrode 30, a sufficient surface area for cauterization can be ensured, and efficient cauterization treatment can be performed.

Further, according to the ablation catheter 100 of this embodiment, the liquid is ejected (irrigated) from the eight irrigation openings 25A arranged at the distal end portion of the irrigation member 20 onto the surface of the distal electrode 30. A sufficient amount of liquid can be brought into contact with the surface of the electrode 30. Moreover, the liquid sprayed onto the surface of the tip electrode 30 flows along the surface of the tip electrode 30 from the base end portion (neck portion 32) of the tip electrode 30 toward the tip portion (tip bulge portion 31). .
Therefore, the ablation catheter 100 has an excellent cooling effect on the surface of the tip electrode 30 and sufficient blood around the tip electrode 30 as compared with a conventionally known catheter in which an irrigation opening is formed in the tip electrode. By further stirring and diluting, a more excellent thrombus formation inhibitory effect is exhibited.
In addition, since the eight irrigation openings 25A are arranged at equiangular (45 °) intervals along the outer periphery of the irrigation member 20, it is possible to irrigate the surface of the tip electrode 30 over the entire region in the circumferential direction (360 °). it can.

Further, in the distal end flexible portion 10A of the catheter shaft 10, the two lumens 11, 11 serving as liquid flow paths, the two lumens 12, 12 serving as insertion paths for the pulling wires 61, 62, and the lead of the ring electrode 40 are provided. Since the two lumens 13 and 13 serving as line insertion passages are both formed in an eccentric position, the leaf spring 65 that could not be arranged by a conventional irrigation catheter having an irrigation member is attached to the catheter shaft. It becomes possible to arrange | position along the center axis | shaft to 10A tip flexible part 10A.
The ablation catheter 100 in which the leaf spring 65 is disposed is excellent in operability by providing sufficient torsional rigidity to the distal end flexible portion 10A of the catheter shaft 10.

  Furthermore, inside the irrigation member 20, there are eight liquid storage spaces 24 that do not have partition walls in the circumferential direction, and eight channels that communicate with the storage space and extend in the distal direction while inclining outward to reach each of the irrigation openings 25A. Since the branch flow path 25 is formed, the liquid that has reached the storage space 24 through the eccentric flow paths 23, 23 is arranged to be uniformly distributed in the circumferential direction in the storage space 24. Since each of the eight branch channels 25 is ejected (irrigated) from the irrigation opening 25A, the amount of liquid supplied from the catheter shaft 10 to the irrigation member 20 varies in the circumferential direction (flexible tip portion). Although there is a variation in the circumferential direction due to the eccentricity of the two lumens 11 and 11 serving as the liquid flow path due to the leaf spring 65 arranged at 10A, the equiangularity ( 45 °) at intervals There is no variation in the amount of liquid ejected between the eight irrigation openings 25A placed, and it becomes possible to perform uniform ejection (irrigation) in the circumferential direction of the irrigation member 20, so that the surface of the tip electrode 30 is surrounded. Irrigation can be performed evenly over the entire direction (360 °).

Further, the rear end side recess 21B (the rear end shape of the first part) formed in the first part 21 and the front end side small diameter portion 221 (the front end shape of the second part) of the second part 22 are fitted. Thus, the irrigation member 20 is configured, and the cylindrical portion 33 of the tip electrode 30 (the rear end shape of the tip electrode) and the tip side recess 21A of the first component 21 (the tip shape of the first component) are fitted. Thus, the tip electrode 30 can be connected to the tip side of the irrigation member 20.
Thus, by comprising the irrigation member 20 by two parts, the problem of the undercut resulting from the shape of the storage space 24 can be avoided, the eccentric flow paths 23 and 23, the storage space 24, and 8 It becomes possible to obtain the irrigation member 20 in which the branch channel 25 of the book is formed by molding.

  Furthermore, since each of the branch flow paths 25 formed inside the irrigation member 20 (first component 11) is formed so as to be inclined outward, the tip electrode (D1 / D2 having a value of 1 / D2 having a certain size is 1). The surface of the tip electrode 30) which is 0.0 can be sufficiently irrigated.

Further, a liquid guide groove 26 extending in the distal direction continuously to each of the branch flow paths 25 is formed at the distal end portion of the irrigation member 20 (first component 11), so that it is ejected from the irrigation opening 25A. The liquid to be guided can be reliably guided (guided) toward the tip electrode 30.
Further, a liquid guide groove 36 that is continuous with each of the guide grooves 26 of the irrigation member 20 is formed on the surface of the proximal end portion of the tip electrode 30, so that it passes through the guide groove 26 formed in the irrigation member 20. The liquid that has reached the proximal end portion of the tip electrode 30 can be guided to the tip portion of the tip electrode 30, whereby the liquid can be supplied to the entire surface of the tip electrode 30.

  Furthermore, a lead wire 40L of the ring-shaped electrode 40 is provided on the outer peripheral surface of the rear end side straight barrel portion (straight barrel portion 213, straight barrel portion 223) of the irrigation member 20 fitted in the distal end side concave portion 15 of the catheter shaft 10. Lead storage grooves (storage grooves 215, shallow groove portions 225a, inclined groove portions 225b, deep groove portions 225c) are formed, and the lead wire 40L of the first ring-shaped electrode 40 from the front end is formed in the front end side recess 15. The lead storage groove enters the shallow groove portion (storage groove 215) from the first side hole formed on the outer peripheral surface, and the lead storage groove (storage groove 215, shallow groove portion 225a, inclined groove portion 225b, deep groove portion 225c). The lead wire 40L of the second ring-shaped electrode 40 from the tip is inserted into the lumen 13 through the second side hole formed in the outer peripheral surface of the tip-side recess 15 from the deep groove of the lead storage groove. Part 25c enters the lumen 13 through this lead storage groove (deep groove portion 225c), so that the distal end side recess of the catheter shaft 10 into which the rear end side straight body portion of the irrigation member 20 is inserted The first and second ring-shaped electrodes from the tip can be attached to the outer peripheral surface of 15.

Thus, the storage groove (storage groove 215, shallow groove part 225a, inclined groove part 225b, deep groove part 225c) of the lead wire 40L is formed on the outer peripheral surface of the rear end side straight body part of the irrigation member 20 for the first time. The ring-shaped electrode 40 can be mounted on the outer peripheral surface of the distal end side concave portion 15 of the catheter shaft 10 into which the rear end side straight body portion of the irrigation member 20 is inserted.
Thereby, for example, the separation distance between the tip electrode 30 (first pole) and the first ring electrode (second pole) from the tip can be shortened (for example, about 2 mm).
It is clinically preferable to measure the bipolar potential between the electrodes arranged at such a short distance.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to these, A various change is possible.
For example, the number of branch channels (irrigation openings) in the irrigation member does not have to be 8, and can be appropriately selected within a range of 4 to 12, for example.
Further, the number of lumens (the number of eccentric flow paths in the irrigation member) serving as the liquid flow path of the catheter shaft may not be 2, but may be 1 or 3 or more. However, the present invention is effective when a catheter shaft having a small number of lumens serving as liquid channels is used.
Also, the internal structure of the catheter shaft is not particularly limited as long as the lumen serving as the liquid flow path is formed eccentrically at the distal end flexible portion.
The shape of the tip electrode is not particularly limited, and may be a shell shape.

DESCRIPTION OF SYMBOLS 100 Ablation catheter 10 Catheter shaft 10A Tip flexible part 11 Lumen (liquid flow path)
12 lumens (Tension wire insertion path)
13 lumens (lead wire passage)
DESCRIPTION OF SYMBOLS 15 Tip side recessed part 20 Irrigation member 21 1st part 211 Reduced diameter part 212 Large diameter part 213 Straight body part 214 Central through-hole 215 Lead wire accommodation groove | channel 21A Tip side recessed part 21a Bottom face (tip surface) of tip side recessed part 21A
21B Rear end side recess 21b Bottom surface of rear end side recess 21B (rear end surface)
22 Second part 221 Tip side small diameter part 223 Straight body part 224 Central through hole 225 Lead wire storage groove 226 Tensile wire storage groove (wire storage groove)
22a Tip end surface of tip side small diameter portion 23 Eccentric channel 231 Stepped portion 24 Liquid storage space 25 Branch channel 25A Irrigation opening 26 Liquid guide groove 30 Tip electrode 30L Lead electrode 31 Tip bulge portion 32 Neck portion 33 Cylindrical portion 35L Temperature sensor lead wire 36 Liquid guide groove 40 Ring electrode 40L Ring electrode lead wire 51 Joint tube 54 Central tube 61 Tension wire 62 Tension wire 65 Leaf spring 70 Control handle 75 Rotating plate 80 Liquid Injection tube

Claims (8)

A catheter shaft having a distal end flexible portion, wherein at least one lumen serving as a liquid flow path is formed eccentrically in the distal end flexible portion; an insulating irrigation member connected to the distal end side of the catheter shaft; An electrode catheter comprising a tip electrode connected to the tip side of the insulating irrigation member,
In the insulating irrigation member, a plurality of irrigation openings for irrigating the surface of the tip electrode with liquid supplied from the catheter shaft are arranged at equiangular intervals along the outer periphery of the insulating irrigation member. ,
At least one ring-shaped electrode is attached to the outer peripheral surface of the distal end flexible portion of the catheter shaft,
In the catheter shaft, at least one lumen serving as an insertion passage for the lead wire of the ring electrode is formed eccentrically at the distal end flexible portion, and the lumen serving as the liquid flow path and the ring electrode A tip side recess is formed with the tip end surface where each of the lumens serving as lead wire insertion passages is open,
The insulating irrigation member is connected to the distal end side of the catheter shaft by fitting the rear end side straight body portion of the insulating irrigation member to the distal end side recess of the catheter shaft,
On the outer peripheral surface of the rear end side straight body portion of the insulating irrigation member, a lead storage groove for storing the lead wire of the ring electrode is formed along the axial direction,
Among the ring electrodes, at least the lead wire of the first ring electrode from the tip is connected to the ring electrode by being joined to the inner peripheral surface of the ring electrode at the tip. Then, it enters the lead receiving groove of the insulating irrigation member from the side hole formed in the outer peripheral surface of the distal end side concave portion of the catheter shaft corresponding to the mounting position of the ring-shaped electrode, and passes through the lead storing groove An electrode catheter, wherein the electrode catheter is inserted into a lumen serving as an insertion passage for the lead wire of the ring-shaped electrode. Inside the insulating irrigation member, at least one eccentric flow path communicating with a lumen that serves as a liquid flow path of the catheter shaft;
A space communicating with the eccentric flow path, and a liquid storage space having no partition wall in the circumferential direction so that the liquid from the eccentric flow path is uniformly distributed in the circumferential direction of the insulating irrigation member; ,
A plurality of branch flow paths communicating with the storage space and extending in the distal direction while inclining outward and reaching each of the plurality of irrigation openings are formed,
A liquid guide groove extending in the distal direction from each of the plurality of irrigation openings is formed in the distal end portion of the insulating irrigation member continuously to each of the plurality of branch channels.
2. The electrode catheter according to claim 1, wherein a liquid guide groove is formed at a proximal end portion of the distal electrode and is continuous with each of the guide grooves of the insulating irrigation member.   3. The electrode catheter according to claim 2, further comprising a leaf spring extending along the central axis of the catheter shaft as a deflection mechanism for deflecting the distal flexible portion of the catheter shaft.   The electrode catheter according to claim 2 or 3, wherein a lumen serving as a liquid flow path of the catheter shaft and an eccentric flow path of the insulating irrigation member communicate with each other via a joint tube. .   The electrode catheter according to any one of claims 2 to 4, wherein the number of eccentric flow paths formed inside the insulating irrigation member is 1 or 2, and the number of branch flow paths is 4 or more. .   The electrode catheter according to any one of claims 2 to 5, wherein the lead storage groove is formed in the order of a shallow groove portion, an inclined groove portion, and a deep groove portion so as to become deeper toward a rear end direction. .   The electrode catheter according to claim 6, wherein the inclined groove portion and the deep groove portion of the lead storage groove are formed on the rear end side from the storage space. The lead wire of the first ring-shaped electrode from the tip enters the shallow groove portion of the lead storage groove from the first side hole formed in the outer peripheral surface of the tip side recess of the catheter shaft,
The lead wire of the second ring-shaped electrode from the distal end enters the deep groove portion of the lead receiving groove from the second side hole formed in the outer peripheral surface of the distal-end-side recess of the catheter shaft. The electrode catheter according to claim 6 or 7, wherein the electrode catheter is characterized.

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